| 摘要 |
<p>PURPOSE:Title composition that contains specific polysiloxanes having vinyl groups and SiH groups respectively and a catalyst amount of platinum compound, thus showing a medium level of releasability from tacky substances without change with the passage of time, and having large residual adhesion. CONSTITUTION:The objective composition comprises (A) 100 parts by wt of an organopolysiloxane that has a viscosity of 40-3,000cps at 25 deg.C and bears 2 or more vinyl groups in the molecule, e.g., dimethylpolysiloxane blocked with vinyl groups at both ends, (B) 0.5-20 parts of an organobydrogenpolysiloxane that has a viscosity of 1-1,000cps at 25 deg.C and 3 or more SiH groups in the molecule, (C) 2-200 parts of a copolymer that consists of R3SiO1/2, R2SiO2/2, and SiO4/2 units (R is monovalent hydrocarbyl) and 2 or more vinyl groups in the molecule and (D) a catalyst amount of a platinum compound.</p> |
